I had an idea the other day and wanted to run it by you guys to see how feasible it would be. I have an old outdoor water fountain pump that you submerge in a pond to pump water into a fountain. I was wondering if it would theoretically be possible to submerge the pump in a bucket of ice water, run the water into my immersion chiller, and the outlet back into the ice water bucket? Would this work? Would it be worth it? Theoretically this would only use roughly 5 gallons of water to chill 108F wort to 70F for pitching. I know I would need to chill it down to that point to begin with, but this seems a more efficient and quicker way to go from 108 down to 70.

I'm going off of the assumption that I would need 5 gallons of ice water (at 32F) to cool 5 gallons of wort from 108F to 70F? As in I take temp of wort and temp of ice water and average them to get the lowest temp I could get without adding more ice. Somebody please check my calculations and understanding of basic chemistry/physics on this one.

a ton of people do this, and yes, it works quite well. the trick is to cool it down to about 100 or below with ground water (takes me about 8-10 min) and then switch over to the submersible pump with the ice water. depending on ambient temp and what kind of wort temp you're going for, 1-2 20lb bags of ice are normally good.

I'm sure it would work, but will it really be quicker for you? your assumption works if you're sending the water from the ice bucket through the chiller and then down the drain. If you recycle the water, you'll start getting progressively lower heat transfer due to the warming of the ice water.

a ton of people do this, and yes, it works quite well. the trick is to cool it down to about 100 or below with ground water (takes me about 8-10 min) and then switch over to the submersible pump with the ice water. depending on ambient temp and what kind of wort temp you're going for, 1-2 20lb bags of ice are normally good.

Yah cool the water a bit first before you start to recirculate. The initial hot water will melt all the ice your pump is in and make that water hot as it recirculates which means you have to change out your water with more cold water and more Ice. I know this from experience But yes, Ice water works great.

a ton of people do this, and yes, it works quite well. the trick is to cool it down to about 100 or below with ground water (takes me about 8-10 min) and then switch over to the submersible pump with the ice water. depending on ambient temp and what kind of wort temp you're going for, 1-2 20lb bags of ice are normally good.

I also use this method, I use 40lb of ice in a cooler and a pond pump, I use the ice water to do all of the chilling and recirculate once I reach 85-90°, but I have to top up the cooler with fresh water from the fridge since my summer tap water is usually over 100°.

I drain my wort through a 20' coil of copper tubing housed inside a bucket of ice water. I chill a couple gallons of water in the fridge, and use it with two 10# bags of ice for a 5 gal batch, and four 10# bags for a 10 gal batch. I can chill from a boil to 70F in the time it takes to drain into the fermenter (~15-30min depending on batch size). I started doing it this way because immersion or counterflow chillers don't work very well here in the summer when the "cold" tap water is close to 100F.

On my last brew I decided not to buy blocks of ice and recirculate. I just filled my mash tun with cold tap water and sent it through my IC. Instead of sending it back to the mash tun I used the hot water and filled my empty kegs and fermenters and used the hot water for cleaning. It worked like a charm. I do not even think it took any longer then when I used ice. Probably because I was not dumping hot water over top of the ice.

I use a Shurflo 12v pump for the task. A pond pump should work good maybe even better because it is a continuous flow pump.

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